Safety device for punch presses



April 20, 1926.

W. A. BROWER SAFETY DEVICE FOR PUNCH PRESS Filed Augusi '7,

3 Sheets-Sheet 1 I avwantoz 7 2255 fl zrawer April 20 1926.

1,581,672 W. A; BROWER SAFETY DEVICE FOR PUNCH PRESSE'S Filed August '7, 1923 3 sheets-Sha 2 avwemtm I 77222 is fl. Brawer April 20 1926.

1,581,672 W. A. BROWER SAFETY DEVICE FOR PUN GH PRESSES Filed August 7, 1923, 3 Sheets-Sheet 3 vwantoz PM?! (15' )Z. Brawer attouwq Patented Apr. 20, 1926.

.wrLLIs A. Bnownza, or ADRIAN, MICHIGAN.

' SAFETY DEVICE FOR PUNCH PRES$ES.

Application filed August 7, 1923. Serial No. 656,228.

To all 107mm itmay concern: 7 Be it known that I, VVILLIs A. Brown, a citizen of the United States of America, residing at Adrian, in the county of Lenawee and State of Michigan, have inventedcertain new and useful Improvements in Safety Devicesffor Punch Presses, of which the following is a specification, reference being bad therein to the accompanying drawings. This invention relates to power operated machines and refers more particularly to safety devices for punch presses.-

An object of the invention is to provide simple and eflicient' latch mechanism for controlling theoperation of the machine.

Another object is to provide reliable and practical mechanism which is adapted to actuate the latch mechanism to operate the machine and which positively requires the use of both hands of the workman to operate. t

lVith the above and other objects in view, the invention consists of certain novel features of construction, combination and arrangement of parts as will be more fully described and particularly pointed out in the appended claims.

In the accompanying drawings Figure 1 is a fragmentary front elevation of a press embodying my invention and showing parts in section;., a Figure 2 is a vertical longitudinal sectional view through thesafety mechanism embodying my invention and showing the parts in normal position;

Figure 3 is a similar view but showing the parts in position after one of the handles has been operated;

Figure 4 is a view similar to Figures 2 l and 3 but showing the mechanism in a position after both handles have been operated;

Figure 5 is a front elevation of the operating handles, support therefor, and connections to the mechanism illustrated in Figures 2, 3 and 4 respectively;

Figure (3 is a top plancview of the construction illustrated in Figure 5;

Figure 7 is a fragmentary side elevation of-the upper portion of the press with the fly wheel removed.

Referring now to the drawings inwhich like characters of reference designate corresponding parts throughout the several views, the numeral 1 designates a press hav ing a table 2, standards 3 extending upwardly from the table and a punch 4 supported from a crank shaft 5 that isjourna'led' in the standards.

The punch is adapted to move vertically to and from the table and for this purposeis preferably provided with a sliding memher 6 that travels in suitable guides 7 upon the standards. A fly wheel 8 is preferably freely rotatably mounted on the shaft 5 at the outer end thereof and is preferably,

driven constantly by suitablemeans (not shown). For connecting the fly wheel to the shaft to actuate the punch, I preferably provide a suitable clutch collar ,9 that is preferably splined upon the shaft "5 and that has outwardly extending projections 10 which are adapted to engagecorresponding: 1y shaped recesses 11 in the inner face of the fly wheel hub 12. A cam 13 is Hprefs era'bly provided on the periphery of the clutch member 9 and is adapted tobe en-' gagcd by a roller 14 at the lower end of a rod 15 slidably mounted in bearings 16' upon one of the standards. The rod is nor-i mally urged downwardly by .meansof a suitable weight 17 so that the roller normally engages'the cam and the clutch collar is normally maintained out of engagement with the hub of the fly wheel. i

Fulcrumed upon the bearing 16 isa relatively short lever 18 that is preferably connected at its inner end to the rod 15 and that is connected at its outer end to a relatively long operating rod 19 which is connected to the operating mechanism of the press. Thus, movement of the rod 19 will cause the lever 18 to raise the rod 15 so i that the roller 14 will be disengaged from the cam 13 whereupon suitable springs 20 will move the clutch collar 9 outwardly to engage the projections 10 with the recesses 11 in the fly wheel hub. The drive connection to the, shaft 5 is then complete to operate the punch. The operation of the punch may be stopped by releasing the rod 19 and permitting the weight 17 to move the rod 15 downwardly sothat the roller 14 will engage the cam 13. The clutch collar 9 will then be moved away from the fly wheel with the result the projections 10 will be disengaged from the recesses 11 and the drive connection to the shaft will be broken. With such constructions it is usual to connect thelower end of the rod 19 to a suitable treadle or foot pedal (notshown) and to providesome form of safety guard-for preventing the handslof the operator being caught between the table 2 of the press and the moving punch. However, it has been found that certain types of guards are not positively fool proof and as a result accidents are liable to occur." I

With the present invention the usual foot pedal and guard are dispensed with, except in such operations which require both hands .to support work outside of the danger zone,

in which case the usualtrip rod 19 connected by suitable means to a foot pedal (not-shown). As a substitute for the pedal operating means, I prefer-ably actuate the rod 19 by means of simple and reliable mechanism which requires both hands of the operator to operate. Thus, the danger of the operators hands being caught between the punch of the press is obviated.

In detail, an elongated casing 21 1s mounted upon one side of the table 2 of the press and is provided with spaced openings 22 in the casing.

the rear end thereof which receives the rods 23 and 24 respectively. The rod 23 1s preferably slidably mounted between a pair of spaced elongated bearing blocks 24 that are supported between vertical plates and 26 respectively, secured by bolts 2"; to the side wall 28 of the casing. Spaced bell crank levers 29 are preferably mounted upon the bottom 30 of the casing and have arms 31 which extend upwardly upon opposite sides of the rods 23 and 24 and which are preferably connectedat their upper ends by a bolt 32. The arms 31 of the bell cranks preferably extend between spaced rollers 33 mounted upon opposite sides of the. rod 23, while a roller 34 is preferably mounted on a pin 35 extending between arms 36 of the bell crank levers and is adapted to travel between a horizontal rod 37 and an elongated sub stantially U-shaped bracket 38 secured to the lower face :of the rod: 37. This rod is preferably provided with an offset portion 39 that is detachably connected to alink 4O which in turn is pivoted to a downwardly projecting extension 41 of a weighted latch member 42 eccentrically mounted upon the sidewall 28 of the'casing.

The latch member is preferably provided at its upper end with a forwardly progectmg arm 43 that extends through an elongated opening 44 in the forwardend of the casing and that is pivotally connected to the lower-- end of the rod 19. An 'adjustabl estop 45 is preferably threaded into the top 21 of the casing and is adapted to limit the upwardly swinging movement of-tlie arm 43, while a recess 46 is preferably provided in the latch member 42 and is adapted to receive the upxer end of a weighted latch finger 47' that is pivotally mounted upon the side wall 28 of Pivotally mounted upon the side wall 28 of the casing is a hook 43 which is connected to the-forward end "of the rod 23 and which norn'iall'y engages a laterally extending pin 49 upon the finger 47 This hook is adapted to be moved by the rod 23 and in turn is adapted to move the upper end of the finger in alignment with the recess 46 in the latch member.

when the rod 23 is moved rearwardly the bell crank levers 29 will be rocked by engagement with the rollers 33 and as a result the roller 34 carried by the arms 36 will raise the rod 37.

For moving the rod 37 rearwardly to rock the latch member 42. so that the recess 46 therein will receive the upper end of the finger 47, I preferably provide projections or lugs 50 and 51 respectively upon the adja cent faces of the rods 3? and 24 for forming clutch like elements whereby the rods 37 and 24 are operatively engaged and disengaged. Thus, when the rod 37 is raised the lug50 thereon will be moved in the path of the-lug 51 on the lower face of the rod 24 suchas shown in Figure 3. When the rod 24 is moved rearwardly the rod 37 will also be moved rearwardly and thus the latch member will be actuated.

W hen the rod 37 moves the latch member about its pivot the recess 46 receives the upper end of the finger 4? and a pin 52 projecting outwardly from simultaneously lifts the l1ook'48 outiof engagement with the pin 49. Thus, when the latch member is permitted to return to normal position and the finger 47 becomes disengaged from the recess 46 the weight 54 will return the finger to normalv position under the latch arm 43. Thus, the linger serves as astop as well as a latch member.

The rods 23 and 24 are adapted to be moved by substantially 'L-shaped handles and 61 respectively which are connected to the rods 23 and 24 by means of bell cranks 62 and rods 63. The handlesare preferably pivoted upon pins 64 extending downwardly from a bracket 65 that is preferably secured to the table of the press, and are preferably located below suitable hand openings 66 iii the bracket. p

In orderthat the rods 23 and 24 respectively will be returned to normal position when the handles 60 and 61 are released, I preferably provide suitable coil springs 55 and 57 that surround the rods 63 between a plate 71 secured to the bracket 65 and suitable collars 72 detachably secured to the rods 63. r I

In use, the handle COis pulled outwardly first which causes the rod 23 to move rearwardly and the rollers33 thereon to move the arms 31 of the bell crank levers 29 rearwardly; Rearward movement of the arms 31 causes the roller. 34 carried by the arms 36, to raise the'rod 37 sothat the projection 50 willbe positioned in the path of the projection 51. Moven'ient of the rod 23 also causes the finger 4'? to be moved by the the latch member nsene'm hook' 48 into: alignment with the recess 46 in thelatch member 42. may then be pulled outwardly to move the rod 24 rearwardly so that the projection 51 will engage the projection and will move the rod 37 rcarwardly. Rearward movement of the rod 37 causes the latch member to move about its pivot so that the recess 46 receives the upper end of the finger 47, while pivotal movement of the latch member 42 causes the arm 43 to move downwardly and to actuate the operating rod 19 and thus cause the lever 18 of the clutch to disengage the roller 15 from the cam 14. Rocking movement of the latch member also causesthe pin 52 to disengage the hook 48 from the pin 49 upon the linger 47.

\Vhen the handles '60 and 61 are released the springs and 57' will restore the rods and 24 to normal position with the result that the rod 37 will be lowered by the "bell crank levers 29 and may be moved forwardly by the downwardly projecting arm 41 of the latchmember when the latch member 42 returns to normal position. The linger 47 will be disengaged from the recess and the weight 54 will move the said finger beneath the arm 43;

in order that no one except authorized persons will be able to have access to the operating mechanism within the casing 21 after the safety device is once installed, I preferably provide a wide closure plate (not shown) which is preferably locked to the casing.

Vhile it is believed that from the foregoing description, the nature and advantages of the invention will'bc readily apparent, I'desire to have it understood thatI do not limit myself to what is herein shown and described and that such changes may be resorted to when desired as fall within the scope of what is claimed.

What I claim as my invention is:

"1. The combination with an operating member of a machine, of a safety devicefor operating said member including a movable element connected to said operating member and provided with a recess, a stop nor-- mally holding said element against movement, means for moving said stop mto alignment with said recess to permit sald element to move, and means for moving said element to cause said operatingimember to I be actuated.

2. The combination with an operating member of machine,- of a safety device for operating said member including a pivotally movable element connected to said operat ing member, a pivoted stop normally holding said element against movement and adapted to move in a plane parallel with that of the said element, means operable by one hand of the operator for moving said The handle 61 rod and the stop about its pivot to permit said element to move,and means operable by the'other hand of the operator for moving said element to cause said operating member to be actuated.

3. The combination with an operating member of a machine, of a safety device for operating said member including a latch member connected to said operating member and having a recess, a latch linger engageable with said recess, means for moving said latch linger in aligni'nent with said recess preparatory to moving the latch member, and means for moving said latch member to cause the recess therein to receive said finger and to simultaneously cause said operating member tobe actuated.

4. In an operating mechanism for ma chines, the coi'nbination with an operating member, of a; latch member connected tov said operating member-and adapted to actuate the same, a stop normally retaining said latch member from moving, a rod, means carried by said rod for moving said stop whereby said latch may be permitted to operate said actuating member, a rod connected to said latch member, an intermediate rod, means for moving the first-mentioned rod, means for establishing an oper ating connection between said intermediate second-mentioned rod, and means for moving the intermediate rod to cause the second-mentioned rod to actuate said latch member.

5. In an operating mechanism for ma-v chines, the combination with an operating member, of a movable latch member connected to said operating member, a stop normally retaining said latch member from moving, a rod, means carried by said rod formoving said stop whereby said latch may be permitted to actuate said operating member, a rod connected to said latch memmove the latter to actuate said latch member. V I a 6. In an operating mechanism for machines, the combination with an operating. member, of a latch member having a pair of arms, one of which is connected to said operating member, means for limiting the movement of the last said arm in one direcating member, and means pivotally engagetion, a stop normallyretaining said latch able with the other of said. arms of the latch member for moving said latch member to, actuate .said operating member. I

7. In an operating mechanism for ma-v chines, the combination with an operating member, of a casing, a movable latch member in said casing and connected to said operating member, a stop in said casing normally retaining said latch member against movement, a member slidably mounted in said casing, a hooked member carried by said slidably mounted member and adapted to move said stop to permit said latch member to actuate said operating member, means latch to actuate said operating member yieldable means normally retaining said hooked member in, engagement with said stop, means for moving said rod to cause said hooked member to move said stop, and means for moving said latch member tov actuate said operating member.

9. In an operating mechanism for machines, the combination with an operating member, of a casing, a movablelatch member in said casing and connected to said operating member, arod slidably mounted in said casing, a hooked member pivoted to said rod and adapted to move said stop to permit said latch to actuate said operating member, means for moving said rod to cause said hooked member to move said stop, means for moving said latch member to actuate said operating member, and means carried by said latchl member for disengaging said hooked member from said stop when said latch member is moved.

10. The combination with an operating member of a. machine, of a safety device for operating said member comprising a. mov-v able latch member connected to said operating member, a stop normally retain ng said latch member from movement, a rod,

hooked member connected to said rod and adapted to move said stop to perm1t saldlatch to actuate said operating member, a-

rod connected to said latch member, an intermediate rod, projections upon said intermediate rodand the second-mentioned rod, a bearing for said intermediate rod, a yieldable means normally retaining the projection on said intermediate rod at one end of the bearing, yieldable means normally re taining said hooked member in engagement with the first-mentioned stop, a bell crank lever loosely connected to the first-mentioned rod and adapted to raise the second-mentioned rod to position the projection thereon in the path of the projection on the inter mediate rod, a handle adapted to move the first-mentioned rod and said bell crank lever, and another handle. adapted to move said intermediate rod to cause the projection thereon to engage the projection on the second mentioned rod and move the latter to actuate the said latch member.

11. The combination, with an operating member of a machine, of a safety device for controlling the operation of the member comprising a latch member connected to the operating member, a stop engaging the latch member, a control rod for moving the operating member through the latch, a second control rod for releasing the stop from engagement with the latch member, and means controlled by the movement of the second mentioned control rod for clutching in or out the connection between the first said control rod and its connection with the latch. I I

12. The combination with an operating member of a machine, of a, safety device for controlling the operation of the member com prising a latch member connected to the operating member, a rod pivoted to the latch member and carrying a clutch element, a

control rod carrying a complementary clutch element for actuating the pivoted rod, and a second control rod formoving the pivoted rod to engage or disengage the said clutch elements.

13. The combination with an operating member of a machine, of a safety device for-controlling the. operation of the member comprising a control rod for moving the operatingmember, said rod including a pair of members provided with complementary clutch elements normally disengaged and a second control rod for engaging said clutch elements. whereupon said first control rod may be actuated to move the operating member. I

let. The combination with an operating member of a machine, of. a safety device for controlling the operation of the member com- Y prising a latch member connected to the operatingmember, a stop engaging the latch member, a control member for mov1ng the operating member through the latch, said rod including a pair of members provided with complementary clutch elements normally disengaged whereby one of the members may be moved fre'elyand independently of the other, and'a second control rod for engaging said clutch elements whereupon said control rod may be actuated to move the actuating member. s

15. The combmatlon with an operating member, of a machine, of a safety device for controlling the operation of said member comprising a control member for moving the operating member, said control member be ing provided with a pair of complementary clutch elements normally disengaged and a second control rod for engaging said clutch elements.

16. The combination with an operating member, of a machine, of a safety device for controlling the operation of said member comprising a control member for moving the operating member, said control member belng provided wlth a pair of complementary clutch elements normally disengaged and a second control rod for engaging sald clutch elements, and means tendlng to always urge said clutch elements into dis- WILLIS A. BROWER. 

